Self-locking nail



July 15, 1952 R 1 HALLOCK 2,603,121

SELF-LOCKING NAILl `Filed Deo. 12, 1945 2 SHEETS-SHEET 1 did@ av Zw? H ed L 5% 36a JZ July 15, 1952 R. HALLocK 2,603,121

SELF-LOCKING NAIL Filed Dec. 12, 1945 2 SHEETS-SHEET 2 F '1:21. I E- f2 a0 7g f4 fa fa' f6' Z BJEETQR,

Patented July 15, i952 UNITED STATESr PATENT OFFICE SELFALOCKING NAIL'- yR'oliertljay Hallock, LarchmonhrN. Y., assgnorto Elastic Stop Nut -Corporatiorrof- America, Union; N. J a corporation of New Jersey Application-.December 12, 1945, Serial-No. 634,485

V(CI.l 85`-1'1) f 19f Claims.

This apphcatlon is. a continuationin partwith respect to my` co-pending applications; S. N'. 568,279, led Decemberl, 1944, andSLN. 578,153, iiled February 16, y1945 (now Patent No.. 2,567,935, granted September. 18, 1951) and relates back thereto as toallcommon subject matter.

The. present invention. relates Ato selflocliing nailsV and has particular reference to nails which achieveV their locking. action. byj distortion to' spreadl apartoffthe nailflaterally when the nail is driven home so as to :grip andholdfin material of such naturetliattle ordinary nailwillnot hold with `sufficient. strength.

The general object of the invention is to provide a novel andirnprovexzll form of nail which'. will aord superior holdingy power in building. materials offa wide variety of kinds suchasrela'- tively soft fibrous wallboard materials', which will also be capable-ofb'eing. driven into and holding in harder materials such' as 'asbestos shingles, pressed. boards of various kinds and the like, whichV will be` usable with frangible materials such as gypsum or plasterboardand the like. and. which4 will be" readily manufacturable by mass production methods at costs comp-arable to the. costs of ordinary nails.

` The manner in which 'the'above stated general object and other objectsoi the inventionare obtained and the advantages to'be .derived from' its use will best be understoodfro'm a consideration of the ensuing portion of this specification taken in conjunction with the accompanying drawings showingfdif'ferent praoticalexamplesof' the invention.

In the'drawings: l i

Fig. 1 is a plan view ofa blankiorformingone kind 'of nailembodying the invention.;

Fig. Z'is a. side elevationofa'nail formed from the blank shown in'Fig; 1;

Fig.' 3 Vis'asection taken on" the line 3-3 of Fig; 2';

Fig. 4 is a section taken onthelinell---` of Fie. 3;'

Fig. 5 ls"a^'view similar; to Fig.`V 3` showing the nail'after being drivenhome inr'elativelysoftma'- teria'l; Y

Fig; 6V is a view similar to'Fig; 5 showing the nail after being drivenfionfie in'rel'ativelyharder' material; v K

Fig: '7- is'a fragmentary lside'elevationtaken. at' right angles to the plane' of Fig. 2` and illustrating' the'head'portion of the-"'nailafter" having been' driven. home; y

Fig. yB'is.v a: viewsimilar toiFi'g 11 showingv the blank foranother kindy of riail'embodyinggthe invention;

` Fig. 9isan end elevation of. the blank shown in' riggs I Fig. `10iA 4is .a .sidlelvatin of.v thelnaillifrmed from', the blank shown. 81;; A

Fig.v 1 1V isan" elevationof the' nail "takenat 'right angles `to FigLlO;

Figs. 12.to 15 inclusive are sections taken on thelrespectively'numberedsection lines of Fig; 10;

Fig. 16' isa longitudinal sectional view showing the nailfof Fig. 10 partially driven into the materialb.

Fig, 1'7 isa, section' similar` to Fig.v 1.6 showing' the knail driven home 1 and Fig.'` 17a' is alsecti'on similarlt'o Fig. 1'7 showing thenail driven home in material thicker than the lengthlof the' nail.

Referring now" more. particularly` to the' nail shownin Figs. 1 to 7',` the'b-lank l for'forming the nail conslstsof al relatively long and narrow' strip ofsheet metal, usually? sheet steel, having parallel sides Vand. apoint" 12S at one end.` In the. central region of thestrip',V there Vis providedl at the .sides vsets of notches Ul;Y I6 and 18;' Adjacentv to the end. of the stripopposite the' pointed end an: aperture 'is formed'in thevblank'which ad.- vantageouslyisof the" chevron' formV indicatz'ed.` Theaperture need n'otbeof. this `speciic lform butthe openingshould be rsoshaped as to provide a projection `preferably pointed, such as the projectionv 22', pointingawayiromthe adjacent endof the blank. Slightlynea'rer to the adgi'acent end ofthe blankV than the.` apertureZ, a second aperture 21k is advantageouslyv provided which in the present embodiment i's'sh'own as a roundhole although itmayihave a diierent configuration.' If desired, the corners ottheblankat theend adjacent tothe aperture 2'may be rounded, or chamfered as shown; Near -itspointed end', the blankv is sheared'to provideanapjerture from which projects asmall projection or 'li'pc'26 point'- ing toward' the Aadjacent endtofithe blank.

By suitable bendingand formingl operations of known kind, the blan'kis shaped' to the form shown in Figs- 2 and 3; Bythese operations, the` blank is* bentalong4` the bendlin'esZ 3, 30 and 32,A to provide-a shank'portionSd', ahead portion .36, formed "by the material between the bendlines 2'8"and 32, and a; shank'portionf'al.,

As will be seen fromVL the drawings, theshank 34is longer than'the shank`38these 'Shanks lying. inadjacent parallel relation' and being connected at the head end'of the nailbya'head'of loop-likev conguration; extending laterally'from the axis off the nail and comprisinglan upper striking pjortion Staf-joiningthe longer'shank Stand a lower aliitment portion l361i joiningthe shorter shank 3 Advantageously, the portionsa and'b ofthe loop1ike^head are 'in the form of hat, plate-'like portions arranged. in V' form `and joinedby an` acute "bend, 'but other Vspecific .coniigurations maybe employed.`

As will further be seen from; the,dra-wingsiA the Shanks-.Stand 38 rare-bent tochannel form; In

the example illustrated, the channel is of generally U-shaped c oniiguration.. but it may be V-shaped or of other suitable c oniiguration providing a channel. The channel section is of primary importance with respect to the longer shank 34 and another cross-sectional configuration of the shorter shank 38 may be employed although a channel section for lthe latteris preferred. The portion of shank 34 extending below the end of the shank 38 is preferably Jcrimped as at 34a. to form a narrower` channel than the main portion of the shank 34.4V By this arrangement, the shank 38 is in eilect received intothe channel of the shank 34 and is substantially sheathed by the shank 34. Advantageously but not necessarily, the lower part of shankY 38 may be slightly flared as indicated at 38a in Fig. 4.

When the blank is bent and formed to produce the finished nail the projection 22, which after the bending operation points toward the head end of the nail, is bent outwardly slightly away from the channel side of shank 38 and the projection or lip 26 projecting fromthe aperture in the shank 34 is bent slightly inwardly toward the channel side of the shank. The two projections, as will be seen from Figs. 2 and 3, abut and in fact overlap. It is" preferable to have these projections overlap as shown but this is not essential so long as the projection 28' is in suchV relation to the projection 22 that the former can act as a stop or abutment for the latter so that the'two projectionsare in eiect in interlocking relation. Among other advantages of having the projections 'overlap is that they act as a retaining means for insuringthat the shorter shank is held securely within'the channel of the longer shank and further it will be seen from Fig. 5 that when the nail is driven, the projection 26 becomes in eiiect the upper wall of the aperture in the longer shank into which the projection 22 projects. Thus the overlapping relation of the lprojections insures the projection 22 being guided and held inthe aperture.

In Fig. 5, the nail is shown driven home in relatively soft material, being shown by way of example as driven into a wallboard or the like 40 of soft fibrous material to which a shingle or the like 42 is held by the nail.

The action of the nail will be largely obvious from comparison of Figs. 3 and 5. When the nail is` driven throughthe shingle and into the board 40 to the extent that the abutment portion 36h of the head comes into contact with the surface of the shingle,the head distorts, the driving and abutment portions of the head bending toward each other to iiatten out the loop as the nail is driven home. When this occurs, it causes relative longitudinal movement between the IShanks, the direction of relative movement being such that the short shank 38 moves toward the head end of the nail relative to the long shank 34. This relative movement causes the projection 26 on the shank 34 to bebent inwardly still further and the projection v22 on shank 38 to move into and rbe held by the wall oi the recess which is in part formed by the projection 26. This action also causes the portion of the shorter shank below the aperture 20 to be bent outwardly away from the axis `of the nail by distortion of the relatively narrow webs 20a at Ythe sides of the aperture 20. The interlocking action of the projections operates to maintain theupper part of the shorter shank 38 in its close relation to the longer shank 34.

When, as in the above described case, the nail is distorted in relatively soft material, the portion 38h of the shorter shank: which is bent outwardly has suncient rigidity to bend to approximately the Vshape shown in Fig'. 5, which is productive of the maximum amount of spread of the nail and consequently the maximum amount of holding power, which is desirable in view of the soft material in which the nail is driven.

In order, however. for the nail to have maximum utility it should be capable of being driven into materialsvof different density and resistance toV the spreading action of the nail. It will be observed that the webs 20a, which are distorted when the portion 38h of the shank is bent outwardly, are relatively narrow and weak. Consequently, if the nail were driven into relatively hard material and had to assume the shape shown in Fig. 5 when driven in such material. the webs 20a might not be strongenough to force the portion outwardly in the material to the extent shown in Fig. 5. For this reason, the aperture 24 is provided to weaken the section of the portion 38b to permit it to yield to an extent determined by the resistance offered by the material into which the nail is driven and in Fig. 6, the action of this weakened section is illustrated. The portion 38h is divided by the weakened section into what may .be termed a heel part 38c and a toe part 38d and as will be seen from the iigure, the weakened section permits the toe part to bend relative to the heel part so that it is not forced so far outwardly into the material. This action does not decrease the eflicacy of the nail since obviously if the material into which the nail is driven is suiliciently densey and resistant to cause the bend between the heel and the toe it will likewise be strong and'` resistant enough to hold the nail against a give'n withdrawing force, with less lateral spread of the nail than would be the case with the nail driven in soft material such as shown in Fig. 5, Vin, which material full spreading of the nail would be effected.

It will thus be seen that' the construction provides a nail of wide applicability for use in materials of different density.4 In some cases where a quantity of nails is desired' for use in a given material, the weakening of the/portion of the shank which is'bent out may be omitted and the extent of the spreading made proper for the material in which the nail is tobe used by proper selection of the distance of the aperture 20 from the free end of the shank. which governs the point of distortion on the shank. By suitably placing this aperture andi the 'corresponding aperture and projection 26, the nail can .be suited to different materials.

As previously noted, the interlocking projections which cause the nail to be distorted serve to retain the portion of the shorter shank above the bending point laterally within the longer shank and advantageously further retaining means are provided at the head end of the nail for preventing relative longitudinal movement between the Shanks in reverse direction after the nail has been fully driven Vand the head collapsed. As will be seen from Fig. 1',`the bending line 32 is offset slightly from the notches I8 and due to this fact, the longer shank 34 is formed with notches at its head endv as Awill be seen'more clearly from Fig. 3. By'reference to Fig. 7, it will be seen that the under portion 36h of the head, which is wider than the channel section of the shank 38 and also of the channel section of the shank 34, lby virtue offthe notches I4, can snap into the recess provided by the notches Il.

This snaps-action. provides` av lock:` preventing4 movement: of'rthe shank. 38I 1in.. a. direction.: away'- from therhead endof the-:nail relative-'to-shanks: 34: after the nail has :been driven.. home.l

In Figs. v85. through 17a', another form*A oifnal embodying the inventionV is.` illustrated;` This;` formis made from pa blankr-fill..havingrzsthe shape:A shown in. Fig. 8 providingl ai; portion; 52.v fory forming the. longer shanki of; 'thea-nail.. which is;

preferably pointed asshownpatz'54:V` The; shortershank isformed from. the portion.. 56 and the;- headv portion y53 lies` between; thefbendflinesLf-B and 6221. The blank. isrprovided withznotches 64V at the bend' line 6.6;A `'Near itsafreerf.endithezshankr portion 56 l"is enlarged to: providefortarraperture 68b which asn shown: is.l round abntznnay haverdif ferent configuration and" at its end; theablank 'ist`V advantageously provided" with'. azbarb 10.' The'. barbed end portion is lconnected-to.themainibody;

of the shank yportieri byY the..y relatively" narrow webs 68a at thesides-ofv the..taperture.=.68.

Thelongervshank 52A is bent: torchannel form-. providing flanges 52a and. 52b1andthe1fshorter shank is also'benttol channel formrhaving ilanges 56d and 5th..r As willbeseen.forrruthedrawings;7 i

the shorter lshank is `received..substantiallyzwithln thev channel. of the :longer'shank :andterminates short' of the sharpenedv on penetratingzend ofthe.: longer shank. Below the;` end. oit"the-'shorter'.v shank', the ilonger' shankrisy advantageouslyfbent' tol form a1 narrower channel; section; 52e.: the;

flanges :ofi the two channel` sections-fof differenti.

widthsbeingV connected by thefinclinedshouilders'VT Z-an'dfM.: Towardithefhead end ofi'thet'nail, ther anges52c and `52h of the'longerz-shankffare bent towardA each` other to providerretaining ears: or

lugs TB'- and 'lwhich overlie. thef'shorter i shank as seenin Figs.. 11 and 132 torretamithegupperportion ofV the shorter shank within* the-channel ofv the 'longer shank. Below theA projections "I Gfand" 7.8," the 'anges of the longer shankareislt trans-- versely inwardly a'short distance from thefed'ges` ofi the channels'`V and the portions*v adjacent to these slitsY on one` side are f bent `inwardly:- along an inclined l-ineltorform inturned projectionsproe viding abutments BIJ-and 8.2 which'zbear against" the wall 'portions 68a forming r'part' ofthe perime eter of aperture 681-in thev shorter:shank:v Thesewall y'portions:providewhat are ln'ect camu sur-- faces adapted to" co'act with etheflabutmentsl y805' and 82fwhichare` in effectrwe'dg-lngfor canifproer jections on the longer shank. In forming the nail, the projections 80 and 82 are formed on the'- iianges ofi the longerV shank' beforey the shorter shank is folded into the-'recessprovided?bythe channel inl the longer shank. Thereafter; the retaining` lugs 16 andv TS1-are bent overeto hold" the parts in assembled relation; andthenarrow ingof the lend'of the channel ofthe-,longer shank" isalso preferably performedafter the'fpartsrarefV in assembled relation so thatr the inclined sh'oul-'r ders '12!andl'14 will bear-lightlyagainst. the sides of the barbed `end 10 of' the shorten-shank and actas aY retaining means-'for'keeping'v the` free end' of this shank within'thechameloflthelonger shank-*until it'is forced out WHenf-thenailisusedlV The headportion158-of the'nailis bent to-loplike 1form `to providefan'upper orstriki'ng portionv 58e and a1' lowerlor labutmerfitportieri 58f and-in the 1 form shown, Ithese portionsofy vthe ,head-'are'- in the-form of hat` plate-likepartsarranged to: form between thenr a V 'joined'byfanfacutebendi Other formsofafheadconiiigurationimaybe-em-e' ployedl. f i

6,? isfillustrated..theiparticulanusefshown;beinggfori attaching ashingle y'llfaoi'hard' materialihaving'a.

pre-formed Vnail -hole e 86: tozfa body.:z of relatively soft fibrous `.material orfthe` like.:` 88.

In Fig.. 16,;` thenail @issshown partially driven to: the point. where the:v abutment.. portion. 58h of thefnail head hascontactlwithfthe surfaceof the shingley and,1acting ast-an abutment," hasapulled the shorter shank 56 relativeirtozthe*longer'shankl j 52 toward the head end of "theifnailg .thisgrelative;

movement beingfpermitted: by: the distortion'. of the vloopelikef headv portion.: Thessv upper 1;' portion` of lthe shorterfshanksisgfretained.withinthe chanf` nelduring Athis movement 1by-rthe1ears. 16,18' and. the-co-action between .the cam;surfacesztprovidedi by the webs 68a and the abutments 8Il,.2;ldistorts.v

the: shorter shank to tenez-ther lower,A end: 56e

outwardly through. the?y bending;- action2v of the..4

relativelyv narrow-"webs` .68a;.

head flat against. the' surfaceA` of `thesl'iinglet and againstA eachfothertoform a:fiat.1nail head; This further distortionof thel'head moves'fthe shorter" shank furtherrelativev tothe? longerrshank andv forces the end'56cffurther laterally.: By -thetime thisvaction has taken` place,=jthe abutments. 80,

82 have reached the'v bottonil :wall Aportion 6815 kof the perimeter of the"aperture-"liBfand.actaslocbingabutments resisting:inwardmovement ofthe projecting lower end. of-'thetdlstorted shank.. The

action is vsimilar in' natureto an'irreversibleicam orworm.

while: m Figs. Y16 anni rmjthenairhas been shown driven' through., a". shingleawitlii au. pre formed nail hole and also throughfsofter 'mate-1A rial having less thickness than the length of the: nail, the utilityrof the'nai'lv is notlimited to such construction and inFi'galla-.theenail' is shown driven throughv azshingle 84a not provided with a pre-formedhole andfintoematerial` 88a.:thicker than the length of the nail.

From the foregoing,- itfwill be:r apparent that b'oth of` the .nails hereinbefore *,described operate in. accordance4 with the samebasi'c principles,Y the major difference in their construction being in.

themeans by` which the 'bending Vor deformation ofthe nail isK accomplished when itis? drivenl home. Inr eachl case.v the rspreading; of? the nail isaccomplished by rela-tive.- longitudinalmove-- ment betweenthe shanksof'the nail; which movement is effected by the distortion or'collapsingof the distortable head whenzthe nail is driven home.

`ItV willV be apparent" thatspecificv details of design can be altered:considerably-as'forexamrelated 'gures; theweakeningbfitheportion ofU the shortershank which lsfforcedV outwardly has not beenlillustrated', itrwill be evident that the'.A

samek arrangement may be. employed as vin the' form: of nail shown in Fig;1 1` and related `gures for making the same. design of nail'applicable for use in materials of dinerentdensities'. In this connection, it is to be notedfthatfinthe.form ofv nail shown in Fig. f 8:aandrrelatedxgures; and

without providing any?. weakenedii-'section' inv the part of i the"shorter"shank.- which .isf-@forced outf wardlyfinto-thefmaterialfilthemaiiicanvreadilyeba designedf-speciiically-vfor'aegiven grade of matei rial by selection of the distance between the ears or tabs 16,18 and the abutmentsll, 82. shorter the distance between these two sets 'of elements, the-greaterwill be the .extent to which the distorted shankis forced outwardly. Consequently, in a naildesigned for use in relatively soft materials, vthis distance shouldbe greater than in a nail 4designed for use .with harder and more resistant'materials. s

While various `specific distortableV structures maybe employed within the scope of the invention to effect' the desired-locking action, the preferred arrangement is., such that the shorter shank is distorted .while the longer shank remains undistorted.v Y V V Regardless of design details, it is characteristic oi the nailthat the spreading action is obtained by bending the lower portionof the holding shank laterally awayfrom .-the, driving shank which has more lateral'rigidity than the holding shank and remains straight, the holding shank having sufficient lateral rigidityto insure its capability of penetratingintoY or through materials of the kind with which it is'vintended to beused.

Also, the. channel form of the driving shank, in addition to providing the desired rigidity against lateral bending, enables the shorter shank to be formed as desiredfor most advantageously effecting its function, without regard to its resistance to. longitudinal compression, since the driving shank,.by in effect sheathing the shorter shank, prevents strong compressive force on the latter whilelthe nail is being driven, which force if excessive might distort the shorter shank or even prematurely tend to collapsethe distortable head.

While as previously noted, the head may take various specific configurations; theform shown is to be preferred since as -will readily be apparent, this form readily Adistorts to provide a at head of substantial area, Ithe size of which can be whatever may be' selected in laying out the blank. Thuswith this form of construction the head area canvbe selected in accordance with the nature of the material with which the nail is tol be used, the softer the material, the larger being the desirable sizeofhead to prevent it pulling through the irnaterial andv also to insure proper collapsing of the head 4when the abutment por-.- tion strikes the surfaceof ,thematerial into which the nail is driven.

Referring again to Fig. l, it will be evident that the nail can be blanked economically from sheet material without appreciable waste by laying out the blanks in endto end relation ,as indicated by the dotted line blankpartsshown at Illa and lub in Fig. 1. Obviously, the same blank arrangement for cutting fromV sheet material can be employed for blanks of the kind shown in Fig. 8.

From the foregoing,it .will be readily apparent that thefinvention is subject to a wide variety of changes and specific; forms of designs and that certain features of construction hereinbefore described may Abe employed to the exclusion of others depending upon the speciiic purpose for which the inail is intended. vThe invention is accordingly to be considered as embracing all forms of construction falling within the scope of the appended claims.. a

What is claimed: i

1. An integral one piecesheet metal nail comprising a driving shank, a holding shank adjacent to said driving shank, lsaid holdingshank being TheV pointed at.the penetrating ,end of the nail andv relatively-irigid. against: lateral bending, a collapsible head connecting said Shanks at'the head end of the,nail,=said head comprising an upper driving portionconnected to said driving shank and Vproviding.a'striking'place adapted to be struck by .a-toolrto drive `the nail and a lower abutmentfgportion connected to said holding shank and. providing an abutment for engaging a worksurface to .causeA said head to collapse when the nail is driven home and thereby produce relative longitudinal movement between the shanks, said holding shank having a relatively weak portion intermediate its ends for establishing a. predetermined. bending place in the shank, and' means comprising aA projection on said holding rshank-anda co-operating aperture in said driving shank. into which said projection extends to engage thegdriving shank and provide a fulcrum point .about which theipenetrating end portion of said :holding shank is caused to bend laterally awayfrom said driving shank upon said relativemovement between the shanks.

2.. An integral one piece sheet metalnail comprising adriving. shankof channel form, a holding shank adjacent toand located at least in part in the channel of .said driving shank, said holding shank being laterally Ibendable and said driving shank being pointed at the penetrating end of the nail and relatively rigid against lateral bending, a .collapsible head connecting said shanks` at the head end of the nail, said head comprisingan. upper driving portion connected to. said driving shank and providing a striking place adapted to be struck by a tool to drive the nail vand a lower abutment portion connected to said holding 'shank and providing an abutment for engaging a work surface to cause said head to collapsewhen, the nail .is driven home and therebi7 produce Arelative longitudinal movement between,the,shanks, said holding shank having a relativelyweakportion intermediate its ends for establishing Va predetermined bending place in the shank, said driving shank having an aperture in the base of .the channel adjacent to said bending place inA said holding shank and said holding shank having a projection extending into said aperture to `engage the driving shank and provide a fulcrum point about which the penetratingnendfportion' of said holding shank is caused;to bend laterallyaway from said driving shank upon said relative movement between the Shanks.,

3. An integral one piece sheet metal nail comprising a laterally relatively rigid driving' shank of channelforrn, a holding shank of channel form substantially nested in the -channel of 'the driving shank, a collapsible head connecting said shanksvatntheheadend of the nail, said head comprising-,anrupper driving portion connected tosaid 1driving shank and providing a striking place adapted tobe struck by a tool to drive the nail, and adower abutment portionconnected to Said holdineishank and providinggan abutment for engaging-,a .work surface to cause said head to collapse when thevnail is driven home and thereby produce .relative longitudinal movement between theshanks, said holding shank having an aperturezintermediate its, ends providing a substantially weakenedv A.portion establishing a predetermined bendiung placeY inV the shank, said driving shankhaving'an aperture in the base of the channel .adjQQnt to saidrbending place in said holding shank, a portion of the perimeter of the laterally-bendable and said driving jshank- .being aperture Iintheholding shank providing 9,.;p1-0- acca-121 vJection extending intothe aperture inthe driving sshank to `engagethe l,drivingshank and provide afulcrum point about which the penetrating end YAYportion `ofssaid'holdi'ng shank is .causedrto bend .laterally away from .said driving shank uponsaid relative movementbetween the Shanks..

4. `Anintegralione Ypiece sheet/metalY nail comprisingla'. drivingl shank of 'channel form, a .holding shank adjacent toy said driving shank, `said holding shank being laterallylbendable and said driving yshank being pointed. at the penetrating end of the nail and relatvelyiigidA against lateral bending, .a .collapsible .head connecting said shanks `at the'head end of the nail, said head comprising an upperJdrivngl portionV connected to said driving shank and providing `a striking place .adapted to'be struck by .a tool to drive the nail :and a lower abutment portion connected to said .holding shank and providing an abutment for engaging 1a. work .surface to. Acause .said head to collapse whenlthe. nailis drivenhome and thereby produce` relative longitudinal .movement between the shanks, saidiholdingshank having an "aperture .intermediateits .ends providing a substantially weakened `portion. establishing .a predetermined bending placjejin .the'shank saiddrivving Shankhavingfan .aperture in the base of the uchanneladjacentIto said bending place in said `holdingshank,.amortion of, the aperture inthe holding shank: providing "a projection extending obliquelytowardthelieadend ofthe nailA into the aperture'in the' drivingfshankto .engage the driving .shank 'toi hold the shanks Alaterally together' at thepplaceofLengagement and v.to provide a fulcrum pointjabout.which the-.penetrating .end portion of said holdin'gishank is causedto bend laterally. awayir'om'said drivngshank upon said vrelative movementjbetween .the Shanks.

5. An'integral one. piece sheet metal nail comprising a driving shank of channel form, a holding shank adjacent 'to 'said driving. shank,. said holding'shank 'beingllaterally bendable and said 4driving Shank" being pointed .at the penetrating 'end of the nail and'relatively rigid against lateral bending, a'jcollapsible head connecting said Shanks atthe head 'endof the nail, said head `comprising an upper driving portion Uconnected to said driving shank' and providing a striking place'adaptedto bestruck'bya tool ,todrive the nai1'and a lower abutment portion `connected to said holding shank and providinganlabutment for engaging `a work surface to cause said head *to collapse when `thc'enailiisdrivenhome `and `"thereby produce vrelative 'longitudinal movement between the shanks, .said holding shank havingV an aperture intermediate its ends providing a substantially weakened .portion lestablishing a predeterminedlbending' place in the shank, said driving shank'having -an aperture inthe base of.

the channel adjacent to said bending place in.l 60

said holding shank, ajportion ofth'e'perimeter of each of said apertures .providing a projection, the projection on the holding .shank `extending obliquely toward'the'head end `of thenail, the

f projection on` the driving ...shank extending. obhquely in the oppositedirection and Ytheitwo projections Vengaging in overlapping relation to hold the Shanks laterally together at the place of engagement and to provide a fulcrum point about which the penetrating end portion of said holding shank is caused to bend laterally away from said driving shank upon said relative movement between the Shanks.

6. An integral one piece sheet metal nail comprising a laterally relatively rigid driving shank fla .of .channel form, va .shorter holding A shank VVsubls'tantiallynested in ,a firstl pbrtonpffthe channel Ofsaid 'dlvn'g'fshalnkg' Said-j liolfling shankbeillg laterally bendable., andI the .fchannel of said driving .snank'-comprismg1-asecpna.portion provided withlapoited end, and .ofismaller cross. section than said'rst portion for., siibstatiallyi-masking the end ,of l.the sliorter holding'- Shank`,'l'a. collapsible' headfconnefcting said'shanksat the head end of thenail, said lhead.cor'nprisfing'` anupper driving portion connected. Y,to VSaid;' jdriving shank and providingastriking placeadapted to .be 'struck by a. tool t1drivejth'e Anail and .la lower abutment portion connected to' VSaidjliolding shank .and

. providingjanab'tment ioren'gag'ingawork sur- 4,face .tocause' 1said.}head .Ito collapse' .when vthe longitudinal vmovement .between .thesli'anks' said `holding shank having a relatively'.vvealdportionintermediate its ends L for establishing... al ,predetermined bendingplace'in' the shankand rneans comprising a projection lon said holding .shank anda co-.operatingfaperturein said. drivingshank into which said) projection extends .to engage `the driving shank and providea A'fulcrum vpoint about which the penetrating end'portionof `said holding shank is caused tobenddaterally awayy from said driving shank upon, saidv relativef'movement between the Shanks. j. a 7. An integral one-piece sheetmetalnail corne prising a driving shank,l a holdingjshankA adjacent to the driving shank'anda 4collapsible" hea .d joining said Shanks /for causing relative longitudinal movement between the shanks when vthe head is collapsed, said ,holding shank having V a I.first weakened place intermediate its ends, means on said Shanks engaging adjacent to said weakened placeto provide a' fulcrumpoint aboutwhch a holding portion of theholding shank; on theside of said weakenedplaceremote from thehead end of the Vnail is caused j to'fbend laterally away Afrom said driving 'shank due toSaid A`relative movement, and said holding shank having a second weakened placefin" s aidholding .portion .to

permit said holding `portion toyield so thatlthe extent of outward movement thereofvis' 'governed by the resistance of the; material into which it is forced. y. 'v

8. An integral one plecesheetmetal,nailcomrprising driving 'andholdingjshanks of channel Aform and a .collapsible head joining; said shanks `for causing relativelon'gitudinal movement between the Shanks when thefheadis'collapsed, said holding shank having an aperture'therein intermediate its ends for substantially weakening the shank to establish a predeterminedfplace `of bending,. means on jsaid vshank engaging to a head of loop like form extending laterally from the axis of the nail and having spaced upper and lower ends, a rst shank depending from said upper end and a second shank depending from said lower end, said head being collapsible to cause said Shanks to have relative movement 1-1 when the head is collapsed to bring said spaced ends together. said rst shankbeing of channel Vsaid portions and `being adjacent to the nrst shank, `said head being collapsible about the apex of the V to cause relative movement between the adjacent shanks, said first shank being of channel form. and narrower than said second portion of said head and the walls of the channel being notched adjacent to the place of juncture between. said first shank and said iirst portion of the head to engage Yand hold the end of said second portion when the head is collapsed.

11. A nail comprising two adjacent shanks of unequal length and a distortable head connecting said shanks, the longer of said shanks providing a channel substantially sheathing the shorter shank and extending beyond the shorter shank at both ends of the latter and providing at one end a sharpened penetrating end for the nail, said head beingof loop-like form providing an upper striking portion joining the head end of the longer shank and a lower abutment portion joining the head end of. the shorter shank, said portions being bent toward v.each other to move the shorter shank relative to the longer shank toward th-e head end of the nail when the nail is driven home, andmeans on said shanks en-VV gaging at a place intermediate the ends of the nail to cause the lower portion of at least one of said shanks to be distorted intermediate its ends and the lower portion thereof bent outwardly away from the axis of the nail due to said relative movement.

12. A nail as set forth in claim 11, in which the portions of said head are shaped to form I between them a V.

13. A nailas set forth in claim- 11 in which the portions ofV said head are of substantially ilat, plate-like form bent -relative to each other to form betweenv them a V.

14. A nail as set forth in claim 11 in which the upper portions of both of said Shanks are of channel section.

15. A nail as set forth in claim 11, in which both of said shanks are of channel section, the longer shank extending below the shorter shank at the penetrative end of the nail and the extending portion of the longer shankfbeing bent to form a narrower channel than that formed in the upper portion of the shank.

16. A nail comprising two adjacent shanks of unequal length and a distortable head connecting said Shanks, the longer of said Shanks providing a channel `for .the Vreception of the upper l2 portion ofthe shorter shank and having means engaging the upper portion of the shorter shank for restraining said portion` against lateral displacementsaid longer shank extending beyond the shorterv shank at'both ends of the latter and providing at one vend asharpenedpenetrating end for the nail, said head being of loop-like form providing an vupper striking portion joining the headV end of the longer shank and a lower abutment portion .joining the head end ofthe shorter shank, said portions being benttoward each other to move the shortershank relative to the longer shank toward the head end of the nail when the nail is driven home, and means on said Shanks engaging at a place intermediate the ends of the nail to causethe lower portion of at least one of said shanks to be distorted intermediate its ends and the lower portion thereof .bent outwardly away from the axis of the nail due to said relative movement.

17. A nail formed from a continuous strip of sheet metal bent toform twoadjacent Shanks of unequallength, the longer shank constituting a driving shank extending beyond the shorter shank atthe head Vend of the nail and having its upper portion formed to channel section,.the shorter shank being disposed in said channel and the head ends of the shanks being joined by a laterally extending head of loop-like form providing an upper, striking -portion joining the longer shank and a lowerV abutment portion joining the Vshorter shank, said portions being bent toward each otherwhen the nail is driven home to move the shorter shank Yrelative to the longer shank toward the head' end'of the nail. retaining means on said longer shank for restraining the upper portion of the shorter shank against lateral movement from the longer shank when said relative movement takesplace, and means on said Shanks engaging below the rst mentioned means for causing lateral distortion of the lower portion of the nail due to said relative movement.

18. A nail as set forth in claim 17 in which the last mentioned means comprises an aperturein the shorter shank providingfa weakened place therein, portions Aof the wall of said aperture providing vcam surfaces and projections on the longer shank engaging said cam surfaces to bend the free end of the shorter shank outwardly away from the longer shank due to said relative movement. i

19. A nail as set forth in claim 18 in which the free end of the shorter shank is provided with a barb.

ROBERTLAY HALLOCK.

' REFERENCES CITED The following references lare of record in the file of this-patent: i y

UNITED STATES PATENTS 

